Lab: DataStage: Read and analyze data from multiple tables

Information Server enables users to better understand their data. It uses pre-built and custom rules that will apply meaning and quality measurements, which are available for users of the data and interested parties.

DataStage Flow Designer enables users to create, edit, load, and run DataStage jobs which can be used to perform integration of data from various sources in order to glean meaningful and valuable information.

This lab will give you hands-on experience using Information Server's datastage flow designer and rule capabilities. In this lab, you will learn the following:

How to join two data sets using DataStage Flow Designer to create a single data set
How to create a data rule that runs on columns from each data set
Apply the rules to the joined data set
View data that does not apply to the rule

This lab is comprised of 2 sections. In the first section, we will see how to associate records within 2 data sets to create a single combined data set using DataStage Flow Designer. In the second section, we will apply a data rule on the combined data set and analyze the data that does not apply to the rule.

Note: The merged data set is already available in DB2WH. If you wish to, you may skip section 1 and directly move on to section 2 where you can import this merged data set.

This lab consists of the following steps:

Section 1: Join the data sets

Section 2: Create and run data rule

Section 1: Join the data sets

Before you start

Before we start the lab, let's switch to the iis-client VM and launch Firefox.

Click on Classic Launchpad in the Bookmarks tab. The first time you try this out, you might see a certificate error. To get past it, click on Advanced... and then click Accept the Risk and Continue.

Click on DataStage Flow Designer.

This brings up the DataStage Flow Designer. Click OK.

1. Create a Transformation project

On the IBM DataStage Flow Designer, click on the Projects tab and click + Create. In the modal that opens up, type in a name for the project and click Create.

The project takes a few minutes to be created and once ready, it will be visible on the Projects tab.

Click on the tile for your newly created project. In the modal that opens up, verify that the name of your project is provided as the Project Name and click OK to switch the project.

2. Add database connection

The input tables - EMP (containing employee data) and DEPT (containing department data) - are already loaded in Db2 Warehouse. Let's add a Db2 warehouse instance as a Connection in DataStage.

Click on the Connections tab and then click + Create to add a new connection.

Provide the following connection details and click OK. Click Save on the new modal that pops up.

Name: DB2WH
Connector type: JDBC
URL: jdbc:db2://db2w-kzwbsid.us-east.db2w.cloud.ibm.com:50001/BLUDB:sslConnection=true;
Username: bluadmin
Password: ****************

A tile for the new connection will now be displayed in the Connections tab.

3. Create the job

Click on the Jobs tab and then click + Create. Click Parallel Job.

A new tab with the name Job_1* opens up where you can now start designing the parallel job.

The first step is to load the input tables DEPT and EMP into DataStage. The WORKDEPT column of the EMP table is the same as the DEPTNO column of the DEPT table.

First, drag a Connection connector to the canvas. In the modal that opens up, select the DB2WH connection that was created earlier and click Next.

On the next screen, select the BLUADMIN schema and click Next.

On the next screen, select the DEPT table and click Next.

On the next screen, click Add to Job.

Drag another Connection connector to the canvas and repeat the steps given above but this time, select the EMP table instead. Once you complete the steps, you should see the two Connection connectors on the canvas.

The EMP table uses the WORKDEPT column to identify the department number whereas the DEPT table uses the DEPTNO column. Use a Transformer stage to modify the output of the EMP table by changing the name of the WORKDEPT column to DEPTNO. This is needed for a future step where we will Join the two tables.

Drag and drop a Transformer stage next to the Connection connector for the EMP table. Provide the output of the EMP table Connection connector as the input to the Transformer stage. For this, click on the little blue dot on the right side of the Connection connector and drag the mouse pointer to the Transformer stage.

NOTE: For another method to connect the Connection connector to the Transformation stage, click on the Connection connector to select it, then drag and drop the Transformation stage. The Transformation stage will automatically be connected to the Connection connector.

Drag and drop a Join stage to the canvas and provide the output of the Transformer stage as the input to this Join stage.

Double click on the Transformer stage to open up the stage page. Go to the Outputs tab and in the table find the entry for the WORKDEPT column. Double click on the WORKDEPT value under the Column name column and replace the text with DEPTNO. Click OK.

Both the tables now have a column called DEPTNO which can be used to join the tables. Provide the output of the DEPT table Connection connector as the second input to the Join stage. Double clicking the Join stage brings up the stage page where you can verify that the DEPTNO is being used as the JOIN KEY and the Join Type is Inner. Click OK.

Drag and drop a Connection connector to the canvas. In the modal that pops up in the screen, check the box for Add selected connection as target and click Add to Job. Provide the output of the Join stage as the input to this connector.

Double click on the Connection connector to open up the Properties page on the right. Verify that the URL, username and password are already populated.

Scroll down and under the Usage section, provide the Table name as <user>_DEPTEMP where \ is your name, and update the Table action to Replace. Click OK.

4. Compile and run the job

Click the Save icon to save the job. If you wish to, you can provide a different name for the job in the modal that pops up. Click Save. Once the job is saved, click on the Compile icon to compile it. If compilation is successful, you should see a green check mark and the message Compiled successfully displayed on the screen.

Click the Run icon to run the job. In the modal that opens up, click Run.

5. View output

After a successful run, the results will be stored within the DB2WH connection in the BLUADMIN schema. Because we specified the Table action as Replace in the Connection connector that represents the output, each subsequent run of the job will delete all existing records in the table and replace them with the new output.

To view the results of the job, double click on the Connection connector that represents the output. This will open up the Properties page on the right. Click on View Data to bring up a modal that shows the contents of the <user>_DEPTEMP table in which the output was stored.

This marks the end of Section 1 of this lab.

Section 2: Create and run data rule

1. Import and view the data

Switch to the iis-client VM and launch Firefox.

Click on the Launchpad bookmark. When the Information Server launchpad shows up click on the Information Governance Catalog New tile.

The overview page will appear.

Click on the Connections tab and click + Create connections.

On the next screen, provide the following details and click Test connection to test the connection. Once successful, click Save connection.

Name: DB2WH
Choose connection: Db2
JDBC URL: jdbc:db2://db2w-kzwbsid.us-east.db2w.cloud.ibm.com:50001/BLUDB:sslConnection=true;
Username: bluadmin
Password: ****************

Now locate the tile for the connection that was just added, click on the kebab icon (⋮) on the tile and click Discover.

Click on Browse.

Expand db2. Expand BLUADMIN and select the <user>_DEPTEMP table where \ is your name. This is the table that was created in section 1 above. If you skipped section 1, then you can select the SANDHYA_DEPTEMP table. Click OK.

Under Discovery options, select Analyze data quality. This will automatically check the boxes for Analyze columns and Assign terms.

Scroll to the bottom and select the Host as IIS-SERVER.IBM.DEMO and the Workspace as UGDefaultWorkspace. Click Discover.

The discovery process will take some time. Once the assets are discovered, the analysis process will begin. Once that completes, you will be able to see what percentage of records were successfully analyzed.

Now let us go and have a look at the data. Go to Quality tab and click on the tile for UGDefaultWorkspace.

The workspace overview will load. Take a few moments to browse the graphics on the page and click on Data sets link to view the data in this exercise.

Before we create new rules, let's look at the data set that will be used in this lab. Click on the tile for <user>_DEPTEMP.

Click on the Columns tab to view findings from the analyzer. It found many things when the data was imported, like maximum and minimum values, distinct values, format, and uniqueness.

We're now ready to create our first data rule!

2. Create a data rule

From the UGDefaultWorkspace workspace, click on the Data rules tab.

Expand Published Rules > 08 Validity and Completeness > Valid Value Combination. Find the rule for IfFieldaIsXThenFieldbGtQty. Click on the ... overflow menu on the right and select Manage in workspace.

The rule should now be available under All. We will now edit the rule. If you wish to rename the rule, you will first need to Copy the rule and you will be provided with the option to rename the rule. Click on the ... overflow menu of the rule and select Edit.

Switch to the Rule logic tab and update the rule to say IF DEPTNAME = 'OPERATIONS' THEN SALARY > 36000.

Next, switch to the Rule testing tab. Here you need to bind the variables in the rule logic to specific columns in the data source. Select the salary variable in the left table and select the SALARY column under Available data sources. It should be under IIS-SERVER.IBM.DEMO > db2 > BLUADMIN > <user>_DEPTEMP. Click on + Bind. The value <user>_DEPTEMP.SALARY will now be shown under Implemented bindings for the salary variable.
Uncheck the salary variable, check the deptname variable and bind it with the DEPTNAME column under Available data sources. As in case of the SALARY column, it should be under IIS-SERVER.IBM.DEMO > db2 > BLUADMIN > <user>_DEPTEMP. Click on + Bind. The value <user>_DEPTEMP.DEPTNAME will now be shown under Implemented bindings for the salary variable.

Scroll down and click on Test to test out the rule. You will see a message at the top of the screen that says the test results can be viewed once ready. When the message disappears, go to the Rule test results tab to view the test results.

You can see that of the 42 total rows, 39 met the rule, and 3 did not. Click on Did not meet rule conditions to view the 3 rows. You can see that these rows have DEPTNAME = OPERATIONS but have SALARY < 36000, and therefore they did not match the rule conditions. Click Save to save the rule.

When you are brought back to the Data rules tab, you'll notice that the new rule has an error. We need to publish the rule. To do so navigate to the right to show the ⋯ menu. Choose the Publish option from the menu.

In the modal that pops up, click Publish to confirm the publish action.

3. Re-analyze and view results

Go back to the UGDefaultWorkspace workspace and click on the Data sets link.

Click on the <user>_DEPTEMP data set.

We can now apply the newly created rule by switching to the Rules (0) tab and clicking the + Add rule button.

Choose the IfFieldaisXThenFieldbGtQty rule under All and click Next.

As before, we need to bind the rule variables to specific columns in our data set. Select the salary variable in the left table and select the SALARY column under Available data sources. Click on the + Bind button. Once bound, select the deptname variable and bind it with the DEPTNAME column under Available data sources. Once both the variables are bound with the right columns, click Next.

This time, we don't need to test the rule. Simply click Save.

You should now see the rule in the data set view. Click on the Analyze button to restart the analysis with the new rule.

In the modal that pops up, click Analyze to confirm analysis.

The analysis will take a few minutes. You may need to refresh your browser a few times. You will see the state go from Running to Successful when analysis is complete.

Once analysis has completed successfully, go to the Data quality tab. You'll see that the new rule has six findings - three against DEPTNAME and three against SALARY. Click on either DEPTNAME or SALARY to view the exceptions.

Scrolling to the right you'll see that the three entries shown have DEPTNAME = OPERATIONS but have SALARY less than 36000, which goes against our rule.

CONGRATULATIONS!! You have completed this lab!

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Last updated 4 years ago

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